Rubber interior decorative unit



Aug.` 1o, 1926. 1,595,581

J. H. STEDMAN RUBBER INTERIOR DECORATIVE UNIT Filed Jan. 215. 1925 enema aeg. in, i926.

JAMES HcSTEDMAN, OF BVBAINTREE, MASSACHUSETTS.

RUIVBBER INTERIOR DECORATIVE UNIT. Y

Application filed January This invention relates to inlaid interior decorative units manufactured from rubber and used for floor tiling, Wall pieces for Wainscoting, border pieces for floors or Walls, and individual pieces of speci-al shape and size to suit a particular use, as an ash tray, saucer, breakfast table tile and the like.

Heretofore such inlaid rubber units have not had any great vogue because of the fact that ordinary rubber compoundsl Will spew at the joint between two adjoining pieces, during vulcanization.

I have discovered a process of making rubber' inlays thatresults in a product having joints that are clean and absolutely speWleSS, thus preserving in the finished'a'rticle all the beauties of outline and other characteristic features of the inlaid ligure.

veution' comprises the process of manufacture hereinafter described andthe novelarticle produced by its practice, its true scope being pointed out in the appended claim.

The accompanying drawing illustrates in Figure l one .inlaid rubber decorative unit that may be produced by practicingr the process, and Fig. .2 is a cross-section, Greatly enlarged, on line 2-2 of Fig. 1, a terrinsertion of the inlayrbut before vulcanication. It will be understood that the limi tations ,of pen and ink delineation prevent a perfect illustration of colors and that the invention includes VWithin its scope an inlay 55 Kwhich ma be com osed. of several ieces properly cut and fitted to forni the desired ligure and \of such. combination of colors as may be pleasing in' an aesthetic' sense or truly representative of the subject as, for.

40 example, the brilliant coloring of a parrot. In practicing the. preferred process of making the rubber inlay a rubbercolor'compound is mixed in accordance with the formula in use at the particular factory 45. with the addition, hgwever, of a fibre content in such percentage as has been found requisite to give the compound a sluggish action -when placed, underA pressure. The fibre reinforcement may conveniently Vbe 5G cotton, as obtained from uncured friction.

scrap of almost any nature, and the rubber steclr may conveniently be prepared in acccrdence with the description found in my Letters Patent of the 'United States No. 1,482,952 for reinforced rubber and 'ln accordancewith this discovery the in.

l$21, 1925. Serial No. 3,825.

process of making the same, dated February 5, 1924.

These compounds, ofvarious colors, are formed into sheets, about one-eighth of an inch thick as linally produced from the calender in the usual mill process, and each sheet is provided with a backing of substantially the same thickness that maybe of the saine material of of ditferent material so that the sheet to be used for the inlay is a-twoply rubber shcet the upper layer at least being reinforced with cotton fibre or the like. The sheets may be vari-colored according to ithe final framing effect desired. Such a sheet, of white rubber, cut; to a square outline is shown in the drawring, the upper ply being indicated by j 10 and the. lower ply or backing being indi.- cated by 12. Y.

The upper ply l0 is then cut through and a piece removed leaving an opening, backed by the ply l2, of the shape of the figure that is to be inlaid. In the.v illustration, the representation of a duck.- 15 is shown as the figure that is to form the inlay, it

being understood that a clean severance 1s made through' the material of the ply l0 in exact duplicationv of the outline of the l iigure chosen for the inlay. In some instances a die may be used but in others the material can better be lremoved by hand cutting. i

The ligure which forms the inlay will be cut inthe same' manner from snot-,her sheet,

but of one ply thickness. This inlay is formed of reinforced rubber and-is of some. contracting color to "She sheet which has been prepared to receive it. As illustrated a black duck l5, having a white eye 18 is inlaid on a White tile as a background as ilf lustrative of one article'that may be pro-A duced..

The gure l5 is out from reinforced rubber that is slightly thicker, by three to've thousandths of an inch, than the ply, 10 so that when placed in the opening-formed in the ply l0 its exposed surface lies in a little higherV plane than the surfaceofthe surrounding sheet {see Fig. 2). This rovides 'i for a perfect hond at the joint 2G etween the two pieces'when pressure is applied in the step of vulcanizing, under heat, in a. press suited to this purpose. This perfectv bond is formed in like manner at any joint between two pieces ef the inlay when more than one color is used in making the figure to beinlaid. After Vulcanization the entire surface is in the same plane.

The shrinkage of reinforced rubber is greater than in unreinforced rubber, being about five-eighths of an inch in fortytwo inches or slightly over one per cent, hence great care must be taken that in cuttingall pieces 'forming a part of the inlay the grain of the fibre runs in the same direction in each when they are assembled. Furthermore, for perfect results, the libre grain in the inlay must likewise run parallel to the libre grain in the sheet prepared to receive the inlay. If these precautions are not taken, when using reinforced rubber, then the heavy shrinkage will occur in different directions and the figure will be distorted. AfterY taking these precautionsithe -finished article presents an inlaid ligure, in true proportion, that stands lout clearly on its background or frame formed by the two-ply sheet.

The beauty and commercial success of the product iS largely due to the use of` rein# forced rubber4 compounds in preparing the various articles. The cotton,'whether spun, raw, cleaned, waste, or other fibrous reinforcing medium functions to resist or retard interlow between the various compounds when y pressure is applied during vulcanization. This retardative medium throughout -the compound elfectually prevents the rubber from spewing atthce joints by slowing up the flow caused by the pressure, the result being a clean joint, showing the true.;.outline of the complete ligure and of all parts thereof that are inlaid in dilferent colors. Practice hasl demonstrated thata it is not possible to obtain these clean joints with unreinforced rubber compounds because the :fiow of this rubber, when under pressure, is wholly uncontrollie, f

The nature and characteristics of the novel" decorative unit having been specifically described and the preferred method of manufacture having been explained, what is claimed as new, is

1. The process of making interior decorative units which includes the step of preparing a two ply sheet of fibre reinforced rubber,cutt"ing out a figure of the desired shape from one ply leaving an opening with the other ply as a backing, cutting out the same ligure for `an inlay from another piece of libre reinforced rubber, slightly thickerA than the ply in which the opening has been cut, inserting the inlay loosely in the opening, and vulcanizing the inlay to the sheet in a suitable mold under suliicient pressure tol produce a smooth inlay surface on the decorative unit.

2. The process of making interior decorative units which includes the step of preparing a sheet of rubber having a front ply and a back ply, the front ply at least being reinforced with a cotton fibre or the like, cutting out a figure of the desired shape from the front ply only, reproducing said ligure for an inlay from another piece or pieces of libre reinforced rubber, slightly thicker than the ply in which the opening yhas been cut, inserting the inlay loosely in the opening, and vulcanizing the linlay to the sheet in a suitable mold under suflicient pressure to produce a smooth inlay surface on the decorative unit. j

3. A rubber interior decorative unit com prising a rubber inlay having a figure of libre reinforced rubber inlaid on a sheet of fibre reinforced rubber, the joint between lthe inlaid ligure and the rubber of the surrounding sheet showing the true outline of the ligure without spewage at. said joint between the inlay and sheet.

4. A rubber interior decorative unit coml -distinct piecesof material abut each other.

JAMES H. STEDMAN. 

